Most automobile seats have two recliner fittings between the seat backrest and the seat cushion (seat part) in order to adjust the angle of the backrest. U.S. Pat. No. 6,991,295 B2 describes a recliner fitting which has been used for many years. This recliner fitting is based on two fitting parts and a locking device with locking elements moved by an eccentric element which is rotated by a hand lever connected to a shaft. The left and the right recliner are connected by a shaft, which is described in U.S. Pat. No. 7,198,330 B2 (D2). The passenger can actuate the hand lever fitted to one end of the shaft, so that the shaft rotates and both recliner fittings are unlocked.
Although the recliner fittings and associated locking devices are robust and capable of use for many years, the locking devices can be exposed to very high loads based on applying high loads to the hand lever. High loads can subject the eccentric and related drive element to unnecessary twist. This can lead to problems including a movement of the hand lever non-use position as well as a movement of the hand lever use position, based on twists and deformation of the connection between the shaft and the locking device.